Process and apparatus for drying veneer



Oct. 14 ,1924.

A. L. DALY PROCESS AND PPARATUS FOR DRYING VENEER Filed Jan. 5.- 1920 2Sheets-Sheet l me/whoa;

A. L. DALY PROCESS ANT) APPARATUS FOR DRYING VENEER Filed Jan. 5. 1920 2Sheets-Sheet. 2

`Patented Oct. 14, 1924.

PAENT QFFIE.

ALEXANDER LYSAGHT BABY, 0F STAPLETON, NEW` YORK.

PROCESS AND PPABATUS FOR DRYNG VENERE.

Application led January 3, 1920. Serial No. 348,253.

To allh whom t may concern:

Be it known that l, ALEXANDER L. DALY, 'a citizen of the United States,vresiding at Stapleton, in the county of Richmond, State 5 of New York,have invented certain new and useful improvements in Processes andApparatus for Drying `Veneer; and l do hereby declare the following tobe a full, clear, and exact description of the'invention, such as willenable others skilled in the art to which it appertains to make and usethe same.

This invention relates to an improved method and apparatus for dryingveneer in a uniform continuous manner.

ln the drying of veneer at the present time, it is customary to pass thesheets of veneer, carried by a belt or belts, between a long series ofheated rolls. Veneer drier's Q0 of this character require a large Hoorspace and are expensive to construct and operate. Jlhe improvedapparatus of the present in vention is simple and inexpensive inconstruction and operation and overcomes the .25 objections to veneerdriers heretofore commonly used. The improved veneer drier of thepresent invention occupies a relatively small `floor space and can beeasily constructed and operated. The improved process of drying veneer,as practiced in this improved apparatus, subjects the veneer sheets orstrips to a continuous and uniform drying operation, followed by asubsequent cooling operation, whereby the dried and cooled veneer stripsor sheets are vdischarged at the end of the dryingand cooling operationin a condition adapted for immediate storage.

A ln the manufacture of veneer, it is custom- 40 ary to use logs ofconsiderable length, for

example, around-17 feet long. These logs 'are commonly quartered, and,after 'squaring or trimming -to .remove the bark and youter edgings orslabs, are cut or sawed into sheets of veneer having ia length equal tothe length-of the log, and having a width varying with the size of thelog. The sheets of veneer thus produced may, for example,

, have a length of'about 17 feet, a width of 30 about 1G inches, more orless, and a thickness of' as little as-one-thirty-second' of an inch orless, the thicknessovf the sheet varygreen logs, it becomes ofimportance to prom vide for the uniform drying of the veneer sheets orstrips 1n a continuous manner.

According to the present invention, thel thin sheets or strips of veneerare fed edgee wise betweenbelts, or series of belts, passing over one ormore series of rolls and subjected to the heating and drying action ofhot air or other heating means; and the sheets are then passed througha. cooling zone where they are cooled by exposure to the atmosphere orartificial cooling means, and then discharged in a cooled and driedcondition so that they can be immediately stacked, shipped, or used.

The invention will be further described in connection with theaccompanying drawings 'illustrative of yone form of apparatus embodyingthe invention and adapted for the practice of the process of theinvention, but it isintended and understood that the invention will beillustrated by, but is not limited to, the specific embodimentsthereofso'illustrated and described.

ln the accompanying drawings- Fig. 1 is a vertical, longitudinal,sectioiial view, of a somewhat diagrammatic character, illustrating theimproved veneer drier;

and

' Fig.- 2 is a vertical, transverse, sectional view taken on the line2-2 of Fig. l.

The apparatus illustrated has a frame Avvlor'kuofl suitable material ciwhich the upright end members are indicated'at l and 2, the top beams at3, and the beams for the feed platform at e. Mounted upon the framemembers et are bearings supporting the rolls 5 and 6 arranged atdifferent levels as shown. A feed table 7a is arranged below the roll 6andx in advance ofthe top of the roll 5.

-Suitably supported by the frame meinn bers or extensions thereof aretwo series of rolls, the rolls 7, 9,'andf12, lland l1 being .arranged atonevend of the apparatus, and .the rolls S, lO'and 13 at the other.Mounted upon these rolls Aare two series of belts 14 and 15. The topbelts 1li pass aroundthe' feed roll 6 andthence successively'around thefous 7,` s, 9, i0, 12 and 13, and back to the feed roll 6. T he lowerbelts^15 pass around the lower feed roll v5 Yand thence successivelyaround the rolls 7, 8, 9, 10, -11 and 'lla, and back to thefeed roll 5.These belts, as shown, .are not laterally continuous, but arespacedapart at regular intervals, the narrow belts of the t-op seriesalternatiig with thenarrow belts of the lower series, and providing aspacetherebetween.

The thin sheets or strips of veneer are fed edgewise upon thelowerseries of belts as they pass over the feed table 7a and are carriedby this lower series of belts beneaththe roll 6, and thence between thetwo series of belts around the rolls 7, 8, -9 and 1 0 and are finallydischarged from the carrying belts upon the discharge table or receivingplatform 28.

The lower'portion of the apparatus, and the' lower rolls and portions ofthe belts earried thereb are enclosedwithin the drying casing or c amberor compartment 16. The

' walls of this chamberor compartment are v belts carrying culated tmade of metal or wood or other suitable materia'l and are provided witha suitable inlet for the introduction of fresh air and a suitableoutletfor the withdrawal` of the hot, f moist air. A conventional inlet 17 isshown at the bottom of'the chamber at'one'end thereof; and' aconventional outletl 18 is shown at fthe to ofthe compartmentat theopposite end, t is opening 18 having the discharge conduits 19 and 19'*connected thereto, -which co duits in turn lead to the exhaust fan20. Sotted openings 24, 25 and' capable of variation and regulation.

In the operation of the apparatus, and the practice of thev improveddrying process, the sheets or stri s of veneer are y,fed edgewise, inthe manner bove described, between the upper and loweseries of belts,

and arethence carried bet een these two series of belts -around the ro s7, 8, 9 and 10. The air -within the drying compartment is suitablyheated by means. of the heating coils or piriles 21 andthis heatedair iscirugh the drying compartment or The fresh air is thus introducedchamber.

Anear the bottom of the compartment through the opening 17 and is heatedby its passage over'th'e heating coils. The heated air comes v incontact with the thin sheets' of veneer and dries. them in a progressivemanner.

Inas- Inuch as the supporting belts are relatively still heatedcondition e numberA and arrangement of these heating pipes or coils is,of course,

exposed .to the direct drying action ofthe heated ai'r. Moreover, theupper and lower belts alternate with each other so that the yentirelength of the veneerstrips will beex posed either on one side or -theother. The y belts are refer-ably of canvas or fabric permitting t ecirculation of air therethrou li so that they do not interfere with theesired heating and drying action. As the veneer strips are carriedaround the end rolls, they are reversedy so that the upper sides of theveneer strips then become the lower sides. In this way, the heated airacts .directly upon first one side of the strips and.

then the other side alternately as the strips are carried successivelyaround the various rolls. Furthermore, the strips are kept in motion s'othat, should portions'of the dry'- ing 'chamber or compartment be warmerthan 'others or shoulda stronger current of heated air be passingthrough certain portions of the compartment, the strips will allnevertheless be subjected t the same drying action because all of 'thesuccessive strips will ybe passed through the drying compartment inthesame manner.

The vveneer strips leave the drying compartment through the slottedopening 25 and then pass around theroll 10 and tothe dis- "chargeplatform or conveyor 28. As the strips leave the dryingl compartment ins t ey are subjected to the 'cooling effect of the outside atmosphere,supplemented by any additional cooling means that may be desired, andthis cooling action continues while the strips are being passed to thepoint of discharge. ,In this manner the strips are thoru hly cooled andfreed lfrom the heat imparte to them 1n the drying compartment.Furthermore, the

cool air, in cooling the strips, exerts a ffurf ther drying influence.

the strips are' removed from the lower belt 15 by. means offin-gers 29,which, as shown, extend part of the way around the roll 11 so that theveneer strips will be forced upon 'the receiving table or conveyor 28Vas the successive. strips are discharged by the belt.

In the diagrammatic illustration ,of Fig. 1, only a few veneer strips 27are shown, and thesearespaced apart at more or less regular, intervals,but it will be understood'that in practice the stripsare fedcontinuously into the machineand that only-a suiiicient space will beleft between the Jacent strips to permit the desired circulation of )airtherebetween.

driving the apparatus can be At the discharge platform or conveyor 28-supplied .from any suitablejso'urce. In the a t rough the belt 30 to theroll 7 and thence` lpparatus illustrated, the power is applied l I theapparatus.

ventionally shown as solid rolls, but it will4 be evident that theserolls need not have any considerable strength or weight, provided theyhave a suiiicient strength to support the belts and the veneer carriedthereby. @penwork rolls having a suitable periphery for the belts willoperate in a similar manner. in order to assist in guiding the twoseries of helts,.one or more of the rolls may -be provided with uideprojections, or with depressions. uide depressions are shown on roller13 in Fig. l2, while similar depressions (not shown) may be provided onroller 11a.

In the operation of the drying apparatus it will be 'understood that theheat applied can be varied by increasing or decreasing the number ofheating pipes or coils or by increasing or decreasing the temperature ofthe heating medium. The drying eiect can also be regulated by increaseor decrease of the draft through the apparatus.

The size of the rolls 7, 8, 9 and 10, around which the veneer is carriedbetween the upper and lower series of belts, is such that the veneerwill pass around the rolls with- Aout being subjected to undue bending.Such bending as is incident to passing around these rolls will bewithstood by the veneer without any objectionable cracking thereof, dueto the fact that the veneer isfed edgewise, so that the bending of theveneer sheets is with the grain rather than across it. As above noted,the veneer strips may have a length of 17 feet or more and a width ofonly about 10 or l2 inches. The apparatus should therefore have asuiicient width to permit the long sheets to be fed sidewisetherethrough. rthat is, the appara-` tus should have a greater width"than the maximum length of the veneer sheets.

l. The method 'or dryingy veneer which comprises feeding the veneersheets edgewise between upper and lower belts, carrying the veneerbetween the belts through a drying compartment and, during suchcarriage, periodically reversing the osition of the sheetsl of veneer tobring their opposite faces alternately uppermost.

2. The method of 'drying veneer, which comprises feeding the veneersheets edge-- wise'between upper and lower belts, with the grain of theveneer substantially perpendicular to the direction of belt travel andpass'- ing the veneer so carried bach and forth around a series of rollsin a drying compartment. l

3. The method ofv drying veneer, which comprises feeding the veneersheets edgewise between upper and lower belts, carryin the veneerbetween the belts back and orth around successive rolls in a dryingcompartment and there subjecting the same to the drying action of heatedair, then carrying the veneer between the belts through cool air, toremove the heat imparted by the dryi ing, and discharging the dried andcooled veneer from between the belts.

4. An apparatus for drying veneer, comprising a series of rolls, seriesof upper and lower endless belts arranged around said rolls and betweenwhich the veneer is to ,be carried, the belts in one set being staggeredwith respect to those of the other set, means for operating said rollsand belts, a drying chamberor compartment enclosing part of said rollsand the belts and veneer carried thereby, and a part of the rolls andbelts being outside said drying compartment kto permit cooling of thedried veneer before discharge from between the belts.

5. An apparatus for drying veneer, comprismg two series of rolls, onenear each end of the apparatus, two series of endless belts arranged torotate around said rolls, a drying compartment enclosing the lower rollsand the belts carried thereby, means for circulating a current of heatedair through said compartment, and the upper rolls and upper portions ofthe belts being voutside said drying compartment and exposed to thecooling action of cool air.

6. An apparatus for drying veneer, oomprising two series of rolls, twoseries of narrowendless belts spaced apart and carried by said rolls,between which the veneer is adapted to be carried, the beltsof oneseries alternating with those of the other so that the veneer only comesincontact with one belt of each series at any particular point of its'length.

7. The method of drying veneer-which comprises moving the sheets inedgewise relation through a drying compartment and, during suchmovement, causing the sheets to passrom one side of the compartment tothe other and'to traverse a curving path in reversing the direction ofthis side to side movement, the sheets being .maintained at al] timeswith their grain substantially 'at right angles to the direction oftheir progress through the compartment whereby the sheets may be lbentyat each change or' direction without liability of breaking.

8. In an apparatus of the character specified, a drying chamber, meansforcarrying the veneer through the chamber and arranged to engage theopposite facesof the sheets Vover restricted areas at points'lrelativelyy far apart and staggered on the `opposite faces.

9. In an apparatus of the character speci-v fied a drying chamber, meansfor ycarrying the veneer through the chamber and ardry, and to reversethe veneer at the end of ranged to engage the opposite faces of the itstravel in each direction whereby to subsheets over restricted areas atpoints relaject the opposite faces of the sheets 'to `a 10 tively farapart and staggered on the opuniform drying action.

' posite faces, said means being arranged to In testimony whereofI aiixmy signature. l

carr the veneer sheets backwards vand forz War s through the chamberuntil they are ALEXANDER LYSGHT-DALY.

